Statement of the problem: The epidemiology of sports-related injury is changing. As the number of high school sports participants increases over time, so do the number and severity of injuries sustained by high school athletes yet the study of injuries in this population has largely been limited by the inability to calculate injury rates, compare findings across groups, or generalize findings from small study samples. Purpose of the proposed research/methods: The long-term goal of this project is to reduce the morbidity, mortality, and disability among adolescent athletes caused by sports-related injuries through the development and implementation of a permanent internet-based high school sports-related injury surveillance system that will consistently produce quality data on high school sports-related injuries, exposures, and risk factors. This project will move toward that goal by pilot testing an internet-based high school sports-related injury surveillance system in a nationally representative sample of US high schools. The specific objectives are: 1) develop an internet-based high school sports-related injury surveillance system, 2) enroll a representative sample of US high schools from which national estimates can be calculated, 3) implement the injury surveillance system for a pilot period of one academic year, and 4) evaluate the system following the pilot period for completeness of reporting and quality of data. Implications for prevention: This project is expected to reduce the morbidity, mortality, and disability caused by high school sports-related injuries within 3-5 years by providing accurate national estimates of injury incidence, injury rates, and risk factor data needed by researchers to develop prevention strategies and by school officials to make effective programmatic decisions. This directly addresses the CDC's mission to promote physical activity and prevent injuries and both directly and indirectly addresses several Healthy People 2010 injury prevention objectives.